Apollo S Computers

The technological marvel that facilitated the Apollo missions to the Moon was the on-board computer. In the 1960s most computers filled an entire room, but the spacecraft’s computer was required to be compact and low power. Although people today find it difficult to accept that it was possible to control a spacecraft using such a ‘primitive’ computer, it nevertheless had capabilities that are advanced even by today’s standards. This is the first book to fully describe the Apollo guidance computer’s architecture, instruction format and programs used by the astronauts. As a comprehensive account, it will span the disciplines of computer science, electrical and aerospace engineering. However, it will also be accessible to the ‘space enthusiast’. In short, the intention is for this to be the definitive account of the Apollo guidance computer. Frank O’Brien’s interest in the Apollo program began as a serious amateur historian. About 12 years ago, he began performing research and writing essays for the Apollo Lunar Surface Journal, and the Apollo Flight Journal. Much of this work centered on his primary interests, the Apollo Guidance Computer (AGC) and the Lunar Module. These Journals are generally considered the canonical online reference on the flights to the Moon. He was then asked to assist the curatorial staff in the creation of the Cradle of Aviation Museum, on Long Island, New York, where he helped prepare the Lunar Module simulator, a LM procedure trainer and an Apollo space suit for display. He regularly lectures on the Apollo computer and related topics to diverse groups, from NASA's computer engineering conferences, the IEEE/ACM, computer festivals and university student groups.

Apollo was built in the era of "big iron" computer mainframes. The concept of an onboard computer for space missions was radically new. There was only one place in the world that could design the Apollo Guidance Computers, and that was MIT. It took most of the U.S.'s production of integrated circuits, another radical idea replacing individual vacuum tubes, to build the AGC's. It took 2,000 person-years of independent code review and validation to ensure that they would operate properly. Besides the technical challenges, the Apollo missions were a matter of National Prestige. In the Space Race between the United States and the Soviet Union, President Kennedy said we were going to the Moon and return safely before the end of the (1960's) decade, so we did. The flight computers for the Saturn launch vehicle were an evolution of earlier missile guidance efforts. The massive Saturn-V first stage was built from clustered Jupiter rockets. The earlier and smaller Saturn-I was built of clustered Redstone rockets, which were themselves a derivative of the early German V-2 rockets by the Von Braun Team. The Saturn's upper stages were all new technology, using liquid hydrogen and oxygen. The vehicle had to achieve and maintain a precise trajectory from its launch site in Florida, to lunar orbit, to the lunar surface and back, and then return to Earth. All this took unprecedented computing power. This book is a brief synopsis of the architecture and applications of the Apollo computers. There is a lot of archived material on the topic, and the list of references in this book is a good starting point. The amazing thing is, the first computer on another world was designed and built before computers were commodity items. It worked as planned. Although your phone has more computing power than the entire Saturn vehicle, you shouldn't trust it to get you to the moon and back.

The race for space begins on October 4, 1957 as the Soviet Union stuns the world and launches the first man made satellite - a feat until then only read about in science fiction. America is caught unprepared for 1957 and must answer this embarrassment to the world by proving its superiority; however, each time America tries to launch a satellite - let alone test a new rocket - it fails. • How could America have taken a back seat in the missile race? • How did America take the lead and win the race to the moon in as little as ten years? • How did America gain the necessary technology and ingenuity to not only launch men into outer space, but also land them on the moon and safely return? • Why did man even go to the moon? • How has the space program affected our lives today? Casey spent his life researching the space program and interviewing many people involved in it, from scientists to astronauts, to find answers to these questions. Casey, an accomplished technical writer, astronomy columnist and artist, began to write this book after he was inspired as a young child when he witnessed, along with the rest of the world, Apollo 11 land three men on the moon in 1969. Casey enjoyed educating students about the space program and wrote this book to share an enthusiasm about science, especially for those never thought about looking up at the night sky and wondering about the stars. Casey wanted students to ask questions and to gain a perspective on how incredible science is. But mostly, he wanted to inspire students to pursue a career in science to continue the peaceful exploration of space for generations to come.

evolution of the Apollo Guidance Computer, Mr. Hall contends that the development of the Apollo computer supported and motivated the semiconductor industry during a time when integrated circuits were just emerging. This was the period just before the electronics revolution that gave birth to modern computers. In addition, the book recalls the history of computer technology, both hardware and software, and the applications of digital computing to missile guidance systems and manned spacecraft. The book also offers graphics and photos drawn from the Draper Laboratories archives that illustrate the technology and related events during the Apollo project. Written for experts as well as lay persons, Journey to the Moon is the first book of its kind and a must for anyone interested in the history of science and the relevance of computer technology to space exploration.

The book reviews developments in the following fields:circular microstrip antennas; microstrip patch antennas; circular polarisation and bandwidth; microstrip dipoles; multilayer and parasitic configurations; wideband flat dipole and short-circuit microstrip patch elements and arrays; numerical analysis; multiport network approach; transmission-line model; rectangular microstrip antennas; low-cost printed antennas; printed phased-array antennas; circularly polarised antenna arrays; microstrip antenna feeds; substrate technology; computer-aided design of microstrip and triplate circuits; resonant microstrip antenna elements and arrays for aerospace applications; mobile and satellite systems; conical conformal microstrip tracking antenna; and microstrip field diagnostics.

The incredible story of how human pilots and automated systems worked together to achieve the ultimate achievement in flight—the lunar landings of NASA’s Apollo program As Apollo 11’s Lunar Module descended toward the moon under automatic control, a program alarm in the guidance computer’s software nearly caused a mission abort. Neil Armstrong responded by switching off the automatic mode and taking direct control. He stopped monitoring the computer and began flying the spacecraft, relying on skill to land it and earning praise for a triumph of human over machine. In Digital Apollo, engineer-historian David Mindell takes this famous moment as a starting point for an exploration of the relationship between humans and computers in the Apollo program. In each of the six Apollo landings, the astronaut in command seized control from the computer and landed with his hand on the stick. Mindell recounts the story of astronauts’ desire to control their spacecraft in parallel with the history of the Apollo Guidance Computer. From the early days of aviation through the birth of spaceflight, test pilots and astronauts sought to be more than “spam in a can” despite the automatic controls, digital computers, and software developed by engineers. Digital Apollo examines the design and execution of each of the six Apollo moon landings, drawing on transcripts and data telemetry from the flights, astronaut interviews, and NASA’s extensive archives. Mindell’s exploration of how human pilots and automated systems worked together to achieve the ultimate in flight—a lunar landing—traces and reframes the debate over the future of humans and automation in space. The results have implications for any venture in which human roles seem threatened by automated systems, whether it is the work at our desktops or the future of exploration.